The present invention solves a problem encountered by rolls of material, such as paper, that are wrapped around a hollow fiber core. The fiber core is typically made from pressed paperboard which has enough rigidity to support the rolled material. When placed on a machine which allows the rolled material to unwind, the fiber core is held and serves as the axis around which the roll of material rotates. Preferably, the unwinding process occurs with stability such that the only motion is rotational.
The manner in which the fiber core is held is critical to the performance of the unwinding process. Typically, a tapered chuck is inserted at each end of the hollow fiber core. The tapered chuck initially exerts a known amount of pressure at its contact points within the hollow fiber core. As the roll is rotated, the dynamic forces associated with the rotation are transferred through the hollow core and into the tapered chuck. Moreover, to maintain a constant rate at which the material is unwrapped, the roll must gradually increase its angular speed as more material is removed from the roll. Ultimately, the increased speeds and dynamic forces result in a marring of the inside surface of the hollow fiber core by the tapered chuck at the contact points. Eventually, the damage to the hollow fiber core may become so great that the severe wobbling of the roll is experienced which can result in a catastrophic failure. Considering that these rolls can weigh from several hundred pounds to several thousand pounds and are rotating at several hundred revolutions per minute, such a failure can result in extensive damage to the machinery and injury to personnel in the immediate area.
One solution to this problem has been to use large metal inserts that fit within the hollow fiber core. However, these metal inserts, which are usually made of steel, weigh thirty pounds or more and are, consequently, difficult to manually transport and position. Moreover, they are expensive since detailed machining is necessary for this insert to tightly fit within the core and perform the necessary process.